Thank you for your query at DoctorSpring.com
Do you have a picture of any of the recent cuts?
When did you start taking the supplements?
Do they appear spontaneously or there is any source of trauma?
Does your lips get dry very easily?
From your description it seems like angular cheilitis, it can be confirmed after i see an image of the cut.
What was your iron level? Vitamin D deficiency is unrelated to the cuts. But it is extremely important you take the supplements properly to prevent bone resorption and joint problems later on.
Once you answer my questions, i will get back to you.